A suffix is a group of letters that is added to the end of a word to make a new word.
Adding the suffix -ness makes a noun which shows a state of being. Tiredness means being tired and feeling the need to rest or sleep.
Can we add 'ness' to any word?
Let's look.
happy - happiness
laugh - laughness
See if you can identify which adjectives we can add 'ness' to using this 2Do.
Remember to read them carefully and see if they sound right.